It is well known that a machine, such as a skid steer loader, typically includes a canopy pivotably mounted to a frame of the machine and mechanically assisted by a gas-charged lift cylinder for movement between closed and open positions. The open position of the canopy allows for access to interior components during maintenance or repair. Therefore, it may be important to hold the canopy in the open position for extended periods of time.
A design disclosed in U.S. Pat. No. 4,811,983 issued to Vern C. Watts, et. al., on Mar. 14, 1989 utilizes a gas spring incorporating a latching stop mechanism. The stop mechanism includes a stop tube mounted to a piston rod and telescopically cooperable with a cylinder body. Two parallel slots extend in a transverse direction through the stop tube. A stop slide has a pair of legs which are adapted to slide within the slots of the stop tube. A release portion of the stop slide is sized to permit the cylinder body to pass between the legs, while a stop portion is sized to prevent the cylinder body from passing between the legs. A spring urges the stop slide toward a stop position at which the stop portion of the stop slide is aligned with the cylinder body when the piston is extended so that the cab enclosure is latched in a tilt-back position. The incorporation of the stop mechanism on the gas spring, however, requires that the gas spring mounting be able to withstand shear forces brought about by loads incurred when the cab enclosure is in the tilt-back position. The shear forces on the gas spring mounting may require additional structural integrity to eliminate damage or possible failure, increasing the cost and weight of the machine.
Additionally, some designs, such as that shown in U.S. Pat. No. 5,547,244 issued to Seung K. Lee on Mar. 14, 1989 utilize an interlocking ring connected to a body of the machine for holding a canopy against pivotal movement. Upon movement from a closed position, the interlocking ring is engaged with an interlocking lug of a hinge block which is connected on the canopy for holding the canopy in an open position. A stopper is used to contact the hinge block as the canopy is pivoted to the open position. The engagement of the interlocking ring with the interlocking lug of the hinge block is not automatic and requires manual assistance. Further, a portion of the loads incurred when the canopy is in the open position may place a shear force on the gas spring mounting or the hinge block mounting which may promote damage or possible failure.
The present invention is directed to overcoming the problems as set forth above.